diff --git a/src/generators/csharp/CSharpGenerator.ts b/src/generators/csharp/CSharpGenerator.ts
index 26a3a94b40..69d66168ab 100644
--- a/src/generators/csharp/CSharpGenerator.ts
+++ b/src/generators/csharp/CSharpGenerator.ts
@@ -54,7 +54,7 @@ export class CSharpGenerator extends AbstractGenerator<CSharpOptions, CSharpRend
   }
 
   constrainToMetaModel(model: MetaModel): ConstrainedMetaModel {
-    return constrainMetaModel(
+    return constrainMetaModel<CSharpOptions>(
       this.options.typeMapping, 
       this.options.constraints, 
       {
diff --git a/src/generators/dart/DartGenerator.ts b/src/generators/dart/DartGenerator.ts
index 98fde73749..9e945f6a23 100644
--- a/src/generators/dart/DartGenerator.ts
+++ b/src/generators/dart/DartGenerator.ts
@@ -49,7 +49,7 @@ export class DartGenerator extends AbstractGenerator<DartOptions, DartRenderComp
   }
 
   constrainToMetaModel(model: MetaModel): ConstrainedMetaModel {
-    return constrainMetaModel(
+    return constrainMetaModel<DartOptions>(
       this.options.typeMapping, 
       this.options.constraints, 
       {
diff --git a/src/generators/go/GoGenerator.ts b/src/generators/go/GoGenerator.ts
index b8209b724c..780c4fbcf9 100644
--- a/src/generators/go/GoGenerator.ts
+++ b/src/generators/go/GoGenerator.ts
@@ -48,7 +48,7 @@ export class GoGenerator extends AbstractGenerator<GoOptions, GoRenderCompleteMo
   }
 
   constrainToMetaModel(model: MetaModel): ConstrainedMetaModel {
-    return constrainMetaModel(
+    return constrainMetaModel<GoOptions>(
       this.options.typeMapping, 
       this.options.constraints, 
       {
diff --git a/src/generators/java/JavaGenerator.ts b/src/generators/java/JavaGenerator.ts
index 034da7fc7f..806247863c 100644
--- a/src/generators/java/JavaGenerator.ts
+++ b/src/generators/java/JavaGenerator.ts
@@ -48,7 +48,7 @@ export class JavaGenerator extends AbstractGenerator<JavaOptions, JavaRenderComp
   }
 
   constrainToMetaModel(model: MetaModel): ConstrainedMetaModel {
-    return constrainMetaModel(
+    return constrainMetaModel<JavaOptions>(
       this.options.typeMapping, 
       this.options.constraints, 
       {
diff --git a/src/generators/javascript/JavaScriptGenerator.ts b/src/generators/javascript/JavaScriptGenerator.ts
index fbd8c7d845..899aaac5bf 100644
--- a/src/generators/javascript/JavaScriptGenerator.ts
+++ b/src/generators/javascript/JavaScriptGenerator.ts
@@ -86,7 +86,7 @@ ${modelCode}`;
   }
 
   constrainToMetaModel(model: MetaModel): ConstrainedMetaModel {
-    return constrainMetaModel(
+    return constrainMetaModel<JavaScriptOptions>(
       this.options.typeMapping, 
       this.options.constraints, 
       {
diff --git a/src/generators/typescript/TypeScriptGenerator.ts b/src/generators/typescript/TypeScriptGenerator.ts
index e3eae34f40..a3b63082cc 100644
--- a/src/generators/typescript/TypeScriptGenerator.ts
+++ b/src/generators/typescript/TypeScriptGenerator.ts
@@ -55,7 +55,7 @@ export class TypeScriptGenerator extends AbstractGenerator<TypeScriptOptions,Typ
   }
 
   constrainToMetaModel(model: MetaModel): ConstrainedMetaModel {
-    return constrainMetaModel(
+    return constrainMetaModel<TypeScriptOptions>(
       this.options.typeMapping, 
       this.options.constraints, 
       {
diff --git a/src/helpers/ConstrainHelpers.ts b/src/helpers/ConstrainHelpers.ts
index bcb11a9510..d6729b17ac 100644
--- a/src/helpers/ConstrainHelpers.ts
+++ b/src/helpers/ConstrainHelpers.ts
@@ -152,7 +152,7 @@ function constrainObjectModel<Options>(typeMapping: TypeMapping<Options>, constr
     const constrainedPropertyModel = new ConstrainedObjectPropertyModel('', propertyMetaModel.required, constrainedModel);
     const constrainedPropertyName = constrainRules.propertyKey({objectPropertyModel: propertyMetaModel, constrainedObjectPropertyModel: constrainedPropertyModel, constrainedObjectModel: constrainedModel, objectModel: context.metaModel});
     constrainedPropertyModel.propertyName = constrainedPropertyName;
-    const constrainedProperty = constrainMetaModel(typeMapping, constrainRules, {...context, metaModel: context.metaModel, propertyKey: constrainedPropertyName});
+    const constrainedProperty = constrainMetaModel(typeMapping, constrainRules, {...context, metaModel: propertyMetaModel.property, propertyKey: constrainedPropertyName});
     constrainedPropertyModel.property = constrainedProperty;
     constrainedModel.properties[String(constrainedPropertyName)] = constrainedPropertyModel;
   }
@@ -178,7 +178,7 @@ function ConstrainEnumModel<Options>(typeMapping: TypeMapping<Options>, constrai
   return constrainedModel;
 }
 
-export function constrainMetaModel(typeMapping: TypeMapping<any>, constrainRules: Constraints, context: ConstrainContext<any, MetaModel>): ConstrainedMetaModel {
+export function constrainMetaModel<Options>(typeMapping: TypeMapping<Options>, constrainRules: Constraints, context: ConstrainContext<Options, MetaModel>): ConstrainedMetaModel {
   const constrainedName = constrainRules.modelName({modelName: context.metaModel.name});
   const newContext = {...context, constrainedName};
   if (newContext.metaModel instanceof ObjectModel) {
diff --git a/test/helpers/ConstrainHelpers.spec.ts b/test/helpers/ConstrainHelpers.spec.ts
new file mode 100644
index 0000000000..8a6e2a92f2
--- /dev/null
+++ b/test/helpers/ConstrainHelpers.spec.ts
@@ -0,0 +1,207 @@
+import { NO_NUMBER_START_CHAR, NO_EMPTY_VALUE, NO_DUPLICATE_PROPERTIES, FormatHelpers, NO_DUPLICATE_ENUM_KEYS, constrainMetaModel, TypeMapping, Constraints } from '../../src/helpers';
+import { AnyModel, ArrayModel, BooleanModel, ConstrainedAnyModel, ConstrainedArrayModel, ConstrainedBooleanModel, ConstrainedDictionaryModel, ConstrainedEnumModel, ConstrainedEnumValueModel, ConstrainedFloatModel, ConstrainedIntegerModel, ConstrainedObjectModel, ConstrainedObjectPropertyModel, ConstrainedReferenceModel, ConstrainedStringModel, ConstrainedTupleModel, ConstrainedTupleValueModel, ConstrainedUnionModel, DictionaryModel, EnumModel, EnumValueModel, FloatModel, IntegerModel, ObjectModel, ObjectPropertyModel, ReferenceModel, StringModel, TupleModel, TupleValueModel, UnionModel } from '../../src/models';
+const mockedTypeMapping: TypeMapping<any> = {
+  Any: jest.fn(),
+  Array: jest.fn(),
+  Boolean: jest.fn(),
+  Dictionary: jest.fn(),
+  Enum: jest.fn(),
+  Float: jest.fn(),
+  Integer: jest.fn(),
+  Object: jest.fn(),
+  Reference: jest.fn(),
+  String: jest.fn(),
+  Tuple: jest.fn(),
+  Union: jest.fn()
+};
+const mockedConstraints: Constraints = {
+  enumKey: jest.fn().mockImplementation(({enumKey}) => enumKey),
+  enumValue: jest.fn().mockImplementation(({enumValue}) => enumValue),
+  modelName: jest.fn().mockImplementation(({modelName}) => modelName),
+  propertyKey: jest.fn().mockImplementation(({objectPropertyModel}) => objectPropertyModel.propertyName)
+};
+describe('ConstrainHelpers', () => {
+  afterEach(() => {
+    jest.clearAllMocks();
+  });
+  describe('constrain ObjectModel', () => {
+    test('should constrain correctly', () => {
+      const testProperty = new StringModel('', undefined);
+      const metaModel = new ObjectModel('test', undefined, {
+        testProperty: new ObjectPropertyModel('testProperty', false, testProperty)
+      });
+      const constrainedModel = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel,
+        options: {},
+        constrainedName: ''
+      });
+      expect(constrainedModel instanceof ConstrainedObjectModel).toEqual(true);
+      expect((constrainedModel as ConstrainedObjectModel).properties['testProperty'].property instanceof ConstrainedStringModel).toEqual(true);
+      expect(mockedConstraints.modelName).toHaveBeenCalledTimes(2);
+      expect(mockedConstraints.propertyKey).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.Object).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.String).toHaveBeenCalledTimes(1);
+    });
+  });
+  describe('constrain ReferenceModel', () => {
+    test('should constrain correctly', () => {
+      const stringModel = new StringModel('', undefined);
+      const metaModel = new ReferenceModel('', undefined, stringModel);
+      const constrainedModel = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel,
+        options: {},
+        constrainedName: ''
+      });
+      expect(constrainedModel instanceof ConstrainedReferenceModel).toEqual(true);
+      expect((constrainedModel as ConstrainedReferenceModel).ref instanceof ConstrainedStringModel).toEqual(true);
+      expect(mockedConstraints.modelName).toHaveBeenCalledTimes(2);
+      expect(mockedTypeMapping.String).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.Reference).toHaveBeenCalledTimes(1);
+    });
+  });
+  describe('constrain AnyModel', () => {
+    test('should constrain correctly', () => {
+      const metaModel = new AnyModel('', undefined);
+      const constrainedModel = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel,
+        options: {},
+        constrainedName: ''
+      });
+      expect(constrainedModel instanceof ConstrainedAnyModel).toEqual(true);
+      expect(mockedConstraints.modelName).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.Any).toHaveBeenCalledTimes(1);
+    });
+  });
+  describe('constrain FloatModel', () => {
+    test('should constrain correctly', () => {
+      const metaModel = new FloatModel('', undefined);
+      const constrainedModel = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel,
+        options: {},
+        constrainedName: ''
+      });
+      expect(constrainedModel instanceof ConstrainedFloatModel).toEqual(true);
+      expect(mockedConstraints.modelName).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.Float).toHaveBeenCalledTimes(1);
+    });
+  });
+  describe('constrain IntegerModel', () => {
+    test('should constrain correctly', () => {
+      const metaModel = new IntegerModel('', undefined);
+      const constrainedModel = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel,
+        options: {},
+        constrainedName: ''
+      });
+      expect(constrainedModel instanceof ConstrainedIntegerModel).toEqual(true);
+      expect(mockedConstraints.modelName).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.Integer).toHaveBeenCalledTimes(1);
+    });
+  });
+  describe('constrain StringModel', () => {
+    test('should constrain correctly', () => {
+      const metaModel = new StringModel('', undefined);
+      const constrainedModel = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel,
+        options: {},
+        constrainedName: ''
+      });
+      expect(constrainedModel instanceof ConstrainedStringModel).toEqual(true);
+      expect(mockedConstraints.modelName).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.String).toHaveBeenCalledTimes(1);
+    });
+  });
+  describe('constrain BooleanModel', () => {
+    test('should constrain correctly', () => {
+      const metaModel = new BooleanModel('', undefined);
+      const constrainedModel = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel,
+        options: {},
+        constrainedName: ''
+      });
+      expect(constrainedModel instanceof ConstrainedBooleanModel).toEqual(true);
+      expect(mockedConstraints.modelName).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.Boolean).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  describe('constrain TupleModel', () => {
+    test('should constrain correctly', () => {
+      const stringModel = new StringModel('', undefined);
+      const metaModel = new TupleModel('test', undefined, [new TupleValueModel(0, stringModel)]);
+      const constrainedModel = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel,
+        options: {},
+        constrainedName: ''
+      });
+      expect(constrainedModel instanceof ConstrainedTupleModel).toEqual(true);
+      expect((constrainedModel as ConstrainedTupleModel).tuple[0].value instanceof ConstrainedStringModel).toEqual(true);
+      expect(mockedConstraints.modelName).toHaveBeenCalledTimes(2);
+      expect(mockedTypeMapping.Tuple).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.String).toHaveBeenCalledTimes(1);
+    });
+  });
+  describe('constrain ArrayModel', () => {
+    test('should constrain correctly', () => {
+      const stringModel = new StringModel('', undefined);
+      const metaModel = new ArrayModel('test', undefined, stringModel);
+      const constrainedModel = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel,
+        options: {},
+        constrainedName: ''
+      });
+      expect(constrainedModel instanceof ConstrainedArrayModel).toEqual(true);
+      expect((constrainedModel as ConstrainedArrayModel).valueModel instanceof ConstrainedStringModel).toEqual(true);
+      expect(mockedConstraints.modelName).toHaveBeenCalledTimes(2);
+      expect(mockedTypeMapping.Array).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.String).toHaveBeenCalledTimes(1);
+    });
+  });
+  describe('constrain UnionModel', () => {
+    test('should constrain correctly', () => {
+      const stringModel = new StringModel('', undefined);
+      const metaModel = new UnionModel('test', undefined, [stringModel]);
+      const constrainedModel = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel,
+        options: {},
+        constrainedName: ''
+      });
+      expect(constrainedModel instanceof ConstrainedUnionModel).toEqual(true);
+      expect((constrainedModel as ConstrainedUnionModel).union[0] instanceof ConstrainedStringModel).toEqual(true);
+      expect(mockedConstraints.modelName).toHaveBeenCalledTimes(2);
+      expect(mockedTypeMapping.Union).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.String).toHaveBeenCalledTimes(1);
+    });
+  });
+  describe('constrain EnumModel', () => {
+    test('should constrain correctly', () => {
+      const metaModel = new EnumModel('test', undefined, [new EnumValueModel('test', 123)]);
+      const constrainedModel = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel,
+        options: {},
+        constrainedName: ''
+      });
+      expect(constrainedModel instanceof ConstrainedEnumModel).toEqual(true);
+      expect((constrainedModel as ConstrainedEnumModel).values[0] instanceof ConstrainedEnumValueModel).toEqual(true);
+      expect(mockedConstraints.modelName).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.Enum).toHaveBeenCalledTimes(1);
+    });
+  });
+  describe('constrain DictionaryModel', () => {
+    test('should constrain correctly', () => {
+      const stringModel = new StringModel('', undefined);
+      const metaModel = new DictionaryModel('test', undefined, stringModel, stringModel);
+      const constrainedModel = constrainMetaModel(mockedTypeMapping, mockedConstraints, {
+        metaModel,
+        options: {},
+        constrainedName: ''
+      });
+      expect(constrainedModel instanceof ConstrainedDictionaryModel).toEqual(true);
+      expect((constrainedModel as ConstrainedDictionaryModel).key instanceof ConstrainedStringModel).toEqual(true);
+      expect((constrainedModel as ConstrainedDictionaryModel).value instanceof ConstrainedStringModel).toEqual(true);
+      expect(mockedConstraints.modelName).toHaveBeenCalledTimes(3);
+      expect(mockedTypeMapping.Dictionary).toHaveBeenCalledTimes(1);
+      expect(mockedTypeMapping.String).toHaveBeenCalledTimes(2);
+    });
+  });
+});